The present invention relates generally to equipment utilized in conjunction with wellsite operations and, in an embodiment described herein, more particularly provides an apparatus for automatically filling a tubular string as it is run in a well.
When a tubular string, such as a work string, completion string or production tubing string, etc., is run in a well, it is generally advantageous for fluid in the well to enter the tubular string as it is being lowered into the well. In this manner, fluid pressure in the tubular string may be equalized with that in an annulus formed between the tubular string and the wellbore, subsequent operations which require fluid in the tubular string are made more convenient, etc. It is not always desirable to fill the tubular string with the fluid in the well, but when it is useful to do so, the ability to automatically fill the tubular string as it is run in the well is particularly advantageous.
In order to ensure successful operations, it is generally considered good practice to pressure test the tubular string periodically as it is being run in the well. However, if the tubular string is open-ended, or otherwise open to fluid communication with the annulus, such as via an opening formed through a sidewall of the tubular string, it may be difficult or uneconomical to periodically close off the opening so that a pressure test may be performed, and then reopen the tubular string so that it may continue to fill while it is lowered further in the well. Additionally, when other items of equipment are pressure tested, such as after setting a packer, it may be advantageous to permit fluid flow through the opening in the tubular string. Thus, it may be seen that the ability to open and close the opening in the tubular string at will to permit automatic filling of the tubular string, pressure testing of the tubular string and pressure testing of other equipment in the well, is very beneficial in these operations.
Furthermore, after the tubular string has been installed and pressure testing concluded, or in other situations, it is sometimes advantageous to prevent fluid flow through the tubular string sidewall. For example, after a production tubing string has been installed it may be desirable to close off any opening through the tubing string sidewall, except at particular locations. Thus, an apparatus which permits automatic filling of a tubular string should, in some cases, have the capability of preventing any fluid flow through a sidewall of the apparatus, whether that flow is directed from the annulus to the interior of the tubular string, or from the interior of the tubular string to the annulus.
From the foregoing, it can be seen that it would be quite desirable to provide an apparatus which permits automatic filling of a tubular string as it is run in a well, which permits convenient pressure testing of the tubular string and other equipment in the well, and which may have the capability of preventing fluid flow through a sidewall thereof. It is accordingly an object of the present invention to provide such an apparatus.